Saeety-top eor railway-cars



2 SheetsSheet 1.

A. POTTS;

. Safety Car.

No. 17,982. Patented Aug. 11. 1857.

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- I Safety Car. No. 17,982. Patented Aug. 11. 1857.

a UNITED STATES "PATENT OFFICE. j

b ALBERT POTTS, OF PHILADELPHIA, PENNSYLVANIA.

SAFETY-TOP FOB, RAILWAY-CARS.

Specification of Letters Patent No. 17,982, dated August 11, 1857.

To all whom it may concern:

Be it known that I, ALBERT Forms, of the city of Philadelphia, in the State of Pennsylvania, have invented a new and useful improvements in the construction of the tops of railway passenger cars, whereby they are made movable and self-acting for the purpose of preventing the loss of human life in the event of many of the most fre quent railroad casualties; and I do hereby; declare that the following is a full, clear, and exact description of the construction? and operation of the same, reference belngf had to the annexed drawings, making a part and its corresponding groove on the side Figure 1 exhibits a side view of a passenger car, showing the manner in whichi it is proposed to disconnect the top from% Instead of having the top permanently attached to the body, as; at present constructed, I join the two toof this specification.

the body of the car.

gether by means of metallic plates, or

'groovedrails, extending around the body? The most convenient place for: these plates, or grooved rails, is immedi-. ately above the doors and windows of the car, as shown at E, F, Fig. 1. These plates or rails in order to give strength to thej body and roof of the car, and to hold thej top securely in its place, may have the form as shown in Fig. 2, where A, B, represents the upper rail, to be fastened to the roof, and E, F, the lower rail to be fastened to, the body of the car, as shown at A, B and of the car.

- the top or roof. The flanges forming these grooves are to be drilled with holes for receiving bolts whereby the same may be securely united to the wood work of the cars as aforesaid. The upper and lower surfaces of these plates which are intended to lie in contact with each other, are formed with the tongue L, and groove K, as shown in Fig. 2-, so as to unite the top with the body and thereby preventing any lateral sliding motion between the two.

The plates across the ends of the cars are made and fastened to the roof and body of the car as above mentioned, but in these end plates the tongue and groove (K, L Fig. 2) are dispensed with and in lieu thereof the uniting surfaces are beveled or angular, as shown in cross section, Fig. 3, where A and B represent the two rails or plates, attached to the top or roof; and G and H, the two lower ones united to the body of the car. The object of having these end plates beveled, or with inclined surfaces, is to prevent any longitudinal sliding of the tops, which might occur from the occasional bumping together of the train. In attaching these end plates to the cars, they may be made to conform to the curvature of the roof as shown at A, B in Fig. 4.

It may be advisable to have the tongue plates, and the bevel, or inclined surface, on the end plates, nearly equal in depth with the flanges on the car wheel.

It will be understood from the above description that the purpose of these metallic plates, or rails, is to retain and hold the top, or roof, firmly in its place on the body of the car, so long as said car maintains a vertical position. But whenever the car loses its center of gravity, either laterally or longitudinally, so as to cause it to fall over on either side, or end, then these tops, or roofs, it is apparent will immediately fall or slide off. Thus in Fig. 6, is exhibited a car which has upset, or fallen over on its side. In Fig. 7 is shown a car plunging end foremost, into a canal, or stream of water at a drawbridge. And in Fig. 8 is presented the position which cars frequently assume fro-m the violence of collision. In each of these respective contingencies it will be readily seen that the effect will be to disconnect the tops, and to throw them off from the body of the car, as illustrated in the said figures.

In order to make these tops, or roofs, perfectly secure on the body of the car, while in a vertical position, against the action of winds, or otherwise, I propose to place at each end of the car over the two end doors, the contrivance as shown in Fig. 3. In this figure O, N is a stout bar, fastened securely against the ends of the car. This bar has a hinge, or rule joint (opening upward only), as shown at O. The outer end N of this bar is made cylindrical, on which is hung the pendulum P, shown enlarged in another position in Fig. 5. In the lower end of the pendulum there is a groove, channel, or recess V. At R is shown a bar, or rail, fastened also to the ends of the car. This bar as shown in Fig. 5 is slightly bent, so as to have the same curva ture as the groove V, in the pendulum described while oscillating on its center of motion N. It will be seen that while the car retains a Vertical position this curved bar remains inserted in the groove V, of the pendulum. Q is a small bar also fastened to the ends of the car, and projecting therefrom so as just to touch the pendulums when the cars are vertical. The motion of the pendulums, it will be understood, is vibratory on the rod N, and also movable in the direction of the dotted lines P, S by means of the rule oint in the bar N, 0. It will now be seen that while the pendulums are in contact with the curved bar or rail R, R, the top cannot be raised upward, but when the car is inclined, or thrown over laterally, the pendulum will then swing clear of the curved bar or are R, R, thus releasing the top and permitting it'to fall off as already described. I

Should the car be inclined longitudinally, as shown in Fig. 7, it is obvious that the pendulum at the upper end of the car, as at F, would fall out in the direction of the dotted line P, S, and release itself from the curved bar R, R; whereas the other pendulum on the lower end of the car, as at E, would be raised by the tendency which the top of the car has in this case to move forward, and thus pressing the pendulumagainst the bar Q would also release it from the catch or curved bar R, R.

In Fig. 9 is shown a modification of the;

weight is to release the pendulum, in the event of an inclination longitudinally, as

shown by the dotted lines, should the car incline in the direction of the arrow. The oscillation of the pendulum P on the bar or lever N, O, is the same in this case as that already described in Fig. 3.

Occurrences may happen in which it may be requisite for the passengers inside to have immediate control or command of the pendulums on the car. Small cords may be attached to the ends of the levers X, and passing thence through a small eyelet hole in the top of the car to the inside as shown at Z.

The advantages to be derived from cars constructed, as above described, will be manifest' in those cases where trains are brought into collision, or tumbled over and precipitated into deep water, whereby the immediate removal of the tops from the body of the cars will afford to the passengers therein instant and ample egression.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The mode or manner of constructing railway passenger cars with the tops and bodies disconnected for the special purpose herein specified.

2. I also claim the metallic plates, or grooved and beveled rails, as above clescribed for uniting the tops with the body of the car as herein above specified.

3. I also claim the combination of the pendulums as fully described in Figs. 3 and 9 for the purpose of holding the tops to the bodies of the cars substantially as herein specified.

ALBERT POTTS.

Witnesses:

CHARLES POTTS, JOHN APPLE. 

